Winch



June 25, 1968 slNn'su slNoHARA ETAL 3,389,891

WINCH lFiled May 5, 1967 IN TOR slmrsu suvon/] Taxes: yoxoynn "manon:Kimm SEIJI KURHUGIH BY Hmvm m vnl/arl MW M ATTORNEYS Unted States PatentO 3,389,891 WINCH Sinitsu Sinoliara, Takesi Yokoyama, Hironori Kimura,Seiii Kurauchi, and Hirorni Miyaucti, Takarnatsn, Japan, assignors toKabushiki Kaislia rliadano Telrkosho, Takarnatsu, Japan Filed May 5,1967, Ser. No. 636,487 Claims priority, application Japan, May 9, 1966,41/43,G38; May 28, 1966, i1/50,tl98; Sept. 21, 1966, 41/S8,964

Claims. (Cl. 254-187) ABSTRACT 0F THE DlSCLOSURE A winch having a rotaryaxis and a winch drum rotated by said rotary axis through theintermediary ot a clutch, a hydraulic cylinder for operating said clutchdevice, first and second hydraulic systems for operating the hoist4motor and the hydraulic cylinder respectively, characterized in thatthe oil pressure set in the second hydraulic system Iincluding saidhydraulic cylinder is raised in synchronism with the rotation of thehydraulic motor, and the clutch device is engaged automatically when thehydraulic motor is rotated by a change-over valve installed in saidtirst hydraulic system.

This invention relates to a winch, and more particularly, to a winchhaving novel driving means.

Heretofore, in the winch of the kind in which the torque of the rotaryaxis rotated by means of a hydraulic motor is 4adapted to be transmittedvia a clutch to a winch drum, rotation of the winch drum in the onedirection or in the other direction was generally effected by rotating ahydraulic motor in the one or hoisting direction or in the other orhoisting down direction and consequently said rotary axis in the desireddirection, through operation of a hydraulic change-over valve installedin the hydraulic system including said hydraulic motor, and `also byoperating a clutch separately 'from the operation of the hydraulicchange-over valve. However, such a winch of the conventional type wasbeset with diiculties such as unnecessary detrition of the clutch sincethe operation of the hydraulic motor was not associated operatively withthe operation of the clutch and the operation of the clutch was notnecessarily carried out while the hydraulic motor remained stationary.

Hence, it is an object o the present invention to provide a -winchhav-ing a rotary :axis and a winch drum rotated by said rotary axisthrough the intermediary of a clutch and so constructed that thehydraulic system for driving said hydraulic motor may be operated insynchronism with the operation of the hydraulic system including theclutch operating mechanism, and the clutch may be operated automaticallyand in association with the driving ot` the hydraulic motor by operatinga hydraulic changeover valve installed in the hydraulic system fordriving said hydraulic motor.

Other objects of the present invention will become apparent from thefollowing description made in conjunction with the accompanying drawingsshowing preferred embodiments ofthe winch of the present invention.

In the drawings:

FIG. l is `an illustrative view showing another embodishowing a winchincluding a rotary axis rotated by means of a hydraulic motor and awinch drum rotated by said rotary axis through a clutch device, and alsoshowing a hydraulic system for operating said rotary axis and saidclutch device;

FIG. 2 is an illustrative view showing another embodiment of thehydraulic system shown lin FIG. 2; and

ice

FIG. 3 is a view similar to FlG. 2 and showing illustratively stillanother embodiment of the hydraulic system.

Referring to the accompanying drawings, especially to FIG. l, a winchmember 1 has a winch drum 2, the outside wall of which is engageablewith a brake band 3 encircling it and the ins-ide wall of which isengageable by a pair of clutch shoes 4, 4' provided inside said winchdrum. Said pair of clutch shoes 4, 4 being pivoted at their ends 6, 7 toa link 5 are thus coupled together, and the other end of the clutch shoe4 is coupled by means of a coupling pin 13 to one end of a double-armlever 11 pivoted lby means of a pivot 10 to a plate 9 secured to arotary axis 8 mounted inside the winch drum 2.

Clutch shoe 4 is pivoted at 12 and the clutch shoes 4, 4 are pullednormally radially inwardly of the winch drum 2 by means of springs 26.The free end of the double-arm lever 11 faces to the foremost end of apiston rod 1S of a hydraulic cylinder 14 secured to said plate 9.Pressure oil for operating the clutch may be delivered at yany time tothe hydraulic cylinder 14 via a pressure oil supply circuit 16 installedthrough said rotary axis 8. When pressure oil is supplied into thehydraulic cylinder 14 via this circuit 16, piston rod 15 -is extended topress against the free end of the double-arm lever 11, which is thenturned about pivot 12 to engage the clutch with the clutch shoes 4, 4displaced outwardly against the force of the spring 26. In this way, therotary axis 8 and the winch drum 1 are operated cooperatively.

Rotary axis 8 is driven by means of a hydraulic motor 17 via a suitablepower transmission device. The construction of a pressure oil supplycircuit to the hydraulic motor 17 as illustrated in the drawingscomprises a pressure oil pump 18, an oil reservoir 19, a centerIlay-pass type two-way hydraulic change-over valve 20, and acounter-balance valve 21 linstalled in a pipe 22 for supplying pressureoil in the one or hoisting direction from the reservoir and intermediatethe hydraulic motor 17 and the 'hydraulic change-over valve 29.Reference number 25 indicates a pipe for supplying pressure oil to thehy- -draulic motor 17 in the other or hoisting down direction. Saidcounterbalance valve 20 is an outside pilot type in which the oilpressure in the pipe 25 is utilized as a pilot pressure thereof.Pressure oil supply circuit 16 to the hydraulic cylinder 14 isconnected, via a hydraulic changeover valve 23, to a part 22a of thepressure oil supply circuit 22 intermediate the hydraulic motor 17 andthe counterbalance valve 21, and is adapted to be cornmunieatedselectively with the pressure oil supply circuit 22a or with the oilreservoir 19 by changeover of the hydraulic change-over valve 23installed therein. In the draw-ings, 24 indicates a check valveinstalled to prevent pressure fluctuations in the pressure oil supplycircuit 16 due to chatter of the check valve 21 which may take placewhen the direction of rotation of hydraulic motor 17 is reversed. 1t isnot always necessary to install Ithis check valve 24, however, where thecounterbalance valve 21 is not liable to chatter.

With the above-mentioned construction of the winch driving meansaccording to the present invention, if the hydraulic change-over valve20 is moved from the neutral position in'the direction indicated by thearrow a, with the hydraulic change-over valve 23 in the positionillustrated in the gure, and the hydraulic motor 17 is rotated in thehoisting direction, oil pressure inside the pressure oil supply circuit22a is raised slightly first of all as a result of resistanceencountered at the start of operation of the hydraulic motor 17. Thus,the hydraulic cylinder 14 connected to this circuit 22a is set intomotion to engage the clutch automatically and to start the winch drum 2in the hoisting direction. When the winch drum 2 is started in thisdirection, oil pressure inside said circuits 22a and 16 is still raised,so that the clutmlteeps on to be engaged and the winch drum 2 keeps onto be rotated in the hoisting direction as long as the hydraulicchange-over valve 20 is maintained in the above-mentioned position. Whenthe hydraulic change-over valve 20 is then returned to the neutralposition, rotation of hydraulic motor 17 and the rotary axis 8 comes toa stop, but the clutch still keeps on to be engaged. When the hydrauliccircuit 16 is communicated with the oil reservoir 19, by operation ofthe change-over valve 23, oil will ilow into the oil reservoir todisengage the clutch and the winch will fall by its own gravity unlessthe brake 3 is applied. y

lf the hydraulic change-over valve 20 is operated in the directionindicated by the arrow a', with the hydraulic change-over valve 23 inthe position illustrated in the ligure, counterbalance valve 21 is notopened and the c-il circuit through, it is not opened so long as the oilpressure inside the oil pipe 25 is raised until a predetermined value isreached, consequently, hydraulic motor 17 cannot start so long as thepressure oil circuits 22 and 2211 are not interconnected. However, whenthe oil pressure inside the oil pipe 2S is raised, and the hydraulicmotor 17 is capable of starting, hydraulic cylinder 14 connected to saidcircuit 22a at 16 is also operated and the clutch is engagedautomatically as in the case of rotation of hydraulic motor in thehoisting direction explained in the foregoing. Thereafter, the clutchkeeps on to be engaged and the winch drum 2 keeps on to be rotated inthe hoisting down direction as long as the hydraulic change-over valve20 is maintained in the above-mentioned position.

As above described, according to the winch driving means of the presentinvention, when thevhydraulic motor 17 is driven in the hoistingdirection or hoisting down direction by operation of the hydraulicchange-over valve 26, clutch is engaged automatically at the. same timewith or shortly before rotation of the hydraulic motor 17, and the winchdrum may be operated in a simple manner in the hoisting or in thehoisting down direction. Since the clutch is engaged at all times whenthe hydraulic motor is stationary, and the latter is started after theclutch is engaged, detrition of the clutch may be minimized. Moreover,the clutch is operated at all times under constant pressure, thejuncture of time at which it comes into play and its working pressureremain constant, and long life o-f the clutch may be ensured.

The hydraulic system illustrated in FIG. 2 is a modication of thatillustrated in FIG. 1, and the corresponding parts are designated by thesame reference numerals.

In this modication, pressure oil supply circuit 16 to the hydrauliccylinder 14 is communi-cated with the pipe 22b intermediate thehydraulic change-over valve 20 and the hydraulic pump 18 via hydraulicchange-over valve 23 and check valve 24. The operation of the hydraulicmotor 17 and the hydraulic cylinder 14 is same as that described withreference to the winch according to the present invention as shown inFIG. 1.

The hydraulic system illustrated in FIG. 3 is a moditication of thatillustrated in FIG. 2, especially of the pressure oil supply circuit 16,and corresponding parts are designated by the same reference marks as inFiGS. 1 and 2. In this modification, a throttle Valve 2S is installed inthe pressure oil supply circuit 16, and a normally closed change-overvalve 23 is installed in a circuit branched from said circuit 16 andcommunicated with oil reservoir 19.

While in the embodiments described in the above with reference to theaccompanying drawings an outside pilot type counterbalance valve, pilotpressure of which is taken from the pipe 25, is used, an inside pilottype counterbalance valve, pilot pressure of which is the oil pressurein the pipe 22, can equally be utilized.

What is claimed is:

1. A winch comprising a rotary axis rotated by a hydraulic motor, awinch drum driven by said rotary axis through the intermediary of aclutch device, a hydraulic cylinder for operating said clutch device, afirst pressure oil circuit connecting said hydraulic motor and an oiltank and including pipes for supplying pressure oil in the one orhoisting direction and in the other or hoisting down direction, a tirstchange-over valve installed in said pressure oil circuit and operativeto stop the tlow of oil through said hydraulic circuit and to regulatethe oil so as to low through said hydraulic circuit in the one orhoisting direction and in the other or hoisting down direction, ahydraulic pump provided in the hydraulic circuit from the reservoirintermediate said change-over valve and oil reservoir, a counterbalancevalve installed in the pipe for feeding oil in the hoisting directionand intermediate said hydraulic motor and change-over valve, a secondpressure oil supply circuit communicating at its one end with saidhydraulic cylinder and at the other end with said pipe for feeding oilin the hoisting direction and including said hydraulic cylinder and asecond change-over valve arranged to selectively return the oil throughit to the oil reservoir; characterized in that the oil pressure set inthe secondly-mentioned hydraulic circuit including said hydrauliccylinder is raised in synchronism with rotation of the hydraulic motorand the clutch device is engaged automatically when the hydraulic motoris rotated in the one or hoisting direction or in the other or hoistingdown direction by operation of said tirst change-over valve.

2. A winch as claimed in claim 1 wherein the pressure circuit includingthe hydraulic cylinder is communicated at one end with said hydrauliccylinder and at the other end with the hydraulic circuit from thereservoir connecting the hydraulic motor and the oil reservoir andintermediate the hydraulic motor and the counterbalance valve.

3. A winch as claimed in claim 1 wherein the pressure circuit includingthe hydraulic cylinder is communicated at one end with said hydrauliccylinder and at the other end with the hydraulic circuit from thereservoir connecting the hydraulic motor and the oil reservoir andintermediate the first change-over valve and the hydraulic pump.

4. A Winch as claimed in claim 1 wherein the pressure oil circuitincluding the hydraulic cylinder comprises a check valve arranged tofeed oil exclusively towards the hydraulic cylinder.

5. A winch as claimed in claim 1 wherein said clutch device includesclutch shoes pivotally mounted on the rotary axis and facing theinternal wall of the winch drum, and a lever connected at one end withone of said clutch shoes and mounted engageably with the piston rod ofthe hydraulic cylinder at the other end.

References Cited UNITED STATES PATENTS 4/1964 Trondsen 254-187 8/1966Schlechter 254-185

